Centrifugal pump



Sept- 11, 1934. H. E. BRoUGH'oN Er AL 1,972,865

GENTRIFUGAL PUMP Filed June 15.` 1931 IIIIIIIII Zhwentors PatentedSept.,11, 1934 i l UNITED STATES PATENT OFFICE CENTRIFUGAL PUMP HaroldE. Broughton and William F. Lamoreaux,

,. Isabella, Tenn.

Application June 15, 1931, Serial No. 544,640 y Claims. (Cl. ID3-103)Our invention relates to improvements in cenof the cylindrical body ofthe supporting section trifugal' pumps, and more particularly to cen-10, we provide a radially extending flange 12 trifugal pumps designed tohandle liquids which which has an outer -face 13 normal to the axispossess densities and/or viscosities greater than of the cylindricalportion. that of water. The casing assembly further comprises a bear- 60It is a primary object of the present invention ing section or member 14having a substantially to provide a centrifugal pump casing assemblycylindrical sleeve disposed in the interior of the which is extremelysimple, compact, and eflicient, cylindrical portion of the supportingsection 10, and which may be easily taken down or assembled. and it alsohas an outwardly extending radial l It is a further object to provide acentrifugal flange 15 which may be secured to and carried 65 pump inwhich the sectional area. of the passage by the flange 12 of thesupporting section. The for the liquid travelling through the pumpdesleeve of the bearing member'may conveniently creases in apredetermined proportion to the inbe provided with a replaceable bushing16, which crease in the velocity imparted to the liquid by is shown asextending the full length thereof.

15 a centrifugal impeller during its flow through the A volute section,represented generally by refer- 70 pump. A ence character 17,constitutes the third principal It is a further object of the inventionto provide element or section of our casing assembly. This an open-sidedimpeller having a desirable rela.- section has certain desirablecharacteristics which tion between curved surfaces and vanes so thatWill now be described.

a, pump is produced which is unusually eflcient A central inlet opening18 communicates di- 75 with liquids of high viscosity and/or density.rectly with an interior substantially cylindrical f A further object isto provide, with such an impeller Chamber 19 in WhiCh the impeller 20,impeller, a casing of peculiar form which has described in vdetailbelow, is mounted for rotaparts cooperating with the impeller in a noveltion. The central inlet yopening 18 communicates' 3 way to produce newresults. with an inlet conduit 21, which is of frusto- 80 Another objectof the invention is to counteract conical shape and ares outwardly,havingr an end thrust which results from the weight of the enlargedopening 22. A discharge chamber 23 parts and from suction during theoperation of is disposed in the peripheral portion of the volute thepump. This object is accomplished by curved section 17, and this chambermay be in substanl surfaces on the impeller, 'as will be pointed outtially the form of a volute,` or any other con- 85 below. ventionaldischarge chamber used with centrifu- In carrying out our invention, weprovide acasgal pumps may be employed. The discharge ing assembly for acentrifugal pump, said aschamber communicates with a discharge passagesemby comprising three principal'elements,which 24 in a conventionalmanner. Above the dis-- may be simply bolted together. Eachof the partscharge chamber we provide a thickened wall 25 90 is constructed ofpeculiar form in order to atto ourvolute section, and on the uppersurface tain the objects of our invention. thereof a plane annularattaching surface 26 is In .the accompanying drawing, an illustrativelocated. As is clearly shown in the drawing, embodiment of the inventionis shown, in which: this surface 26 is bolted to the outer portion ofFigure 1 is a vertical elevation of a pump emange 12 on supportingsection 10. An appro- 95 bodying our invention, the pump being submerged.priate gasket 27 should be interposed between in a tank, and the tankbeing shown in section. the surface 26 and flange 12 to prevent leakage4 Figure 2 is a vertical sectional view of our imof uid along thisjoint.

proved Centrifugal Dump- Another important feature of the volute sec-Figure 3 iS a bottom plan view. tion resides in the fact that theimpeller chamber 100 It iS t0 be UIIdeIStOOd that the apparatus ShOWIlthereof is provided with a substantially plane in the accompanyingdrawing is an illustrative interior surface 28 normal to the axis of theembodiment only of our invention, and that the pump and extending fromthe imei; opening 18 invention is not to be limited to the specific conoutwardly to the discharge chamber 23. l struction shown, but'is to begiven a scope equal The impeller of our invention is entirely open 105to that dened by the accompanying'claims. on one side and closed on theother side by a In the device of the drawing, we have shown backingmember 29. This backing member, or a pump casing assembly comprising asupporting body portion of the impeller, has on its front section 10having a cylindrical body and secured face a plurality of vanes orblades 30 which may i at its upper end to a. stand 11. At the lower endbe radial with respect to the impeller or may be curved rearwardly inaccordance with well known centrifugal pump practice, asvshown in dottedlines in Figure 3. The blades 30 project from the front face of theimpeller body, as aforesaid, and their front edges terminate in 4a planewhich is normal to the plane of the terior surface 28 of the casing 17and is parallelthereto. The front surface of the impeller curves fromthe point 31 away from the plane .surface 28 throughout the centralportion of the impeller and then, approximately at point 32, commencesto curve toward said plane and continues to do so throughout theremaining peripheral portion of the impeller.

The impeller described above is shown in the drawing as being secured toan axial driving shaft 33 connected to a suitable electric motor 34. Therear face of the impeller is provided with a shoulder 35 which extendsacross the end of bushing 16 and has a thrust t with an annulardepression 36 in bearing member 14.

It will be seen that this construction of the impeller with respect tothe casing in which it rotates provides a passage for the liquid beingpumped, which passage gradually decreases in sectional area from theinlet to the outlet, and in a predetermined proportion to the increasein the velocity of \the liquid being worked onbyI entire path of theliquid into variel through the\ impeller is stream-lined and of suitablydecreasing area., the efllciency of the pump is greatly improved.

'Ihe curvature of the impeller surface is so proportioned as to developthe desired velocity of liquid flow with respect to the peripheral speedof the impeller varies. Furthermore, the centrifugal flow of the liquidagainst the curved front surface of the impeller exerts an upward liftthereupon more than sufficient to balance the downward .thrust due tothe weight of the impeller and shaft, and consequently there ismaintained a constant contact between the shoulder 35 and the vbearingmember at point 36, thereby preventing any vertical movement of theseparts. This upward thrust causes the floating impeller to rotate in afixed horizontal plane and prevents end play during the operation of thedevice.

From a manufacturing point of view, the pump casing assembly Y shown inthe accompanying drawing and described above, presents many advantages.The meeting surfaces of the various parts are all exposed during themanufacturing process, and consequently may be conveniently andaccurately machined on standard lathes so that an accurate fit betweenthe various parts may readily be accomplished. The threepart assembly ofthe casing is extremely simple and may be taken down or assembled forinstallation,'removal or repair with ease by merely removing the bolts3'?.

It will be seen by one skilled in the art that all of the objects of ourinvention are accomplished by a device made in accordance with thedescription given above when considered with the accompanying drawing,and that `an exceeding novel,

simple, and efficient centrifugal pump is provided..

.We claim:

1. In a centrifugal pump, a casing having .a

central inlet opening and an outwardly projecting inlet conduit adjacentsaid opening, said conduit being frusto-conical in form and having itssmaller end adjacent said opening in said casing, said casing having aperipheraldischarge chamber and a plane interior surface extendingradially from said opening to said discharge chamber, said pump havingan open-sided impeller in said casing coaxial with said inlet openingand having its open side facing said plane interiory surface y of saidcasing and a plurality of rearwardly curved blades projecting from theopen side and extending continuously from substantially the center ofthe impeller to the periphery thereof, said frontloo said impeller assaid surface approaches said peripheral discharge chamber. f

2. An opensided impeller for use with a centrifugal pump having a fixedaxis on which said impeller rotates, said pump having an axial inlet anda peripheral discharge, said impeller comprising a backing member havinga curved front surface facing said inlet and a plurality of rearwardlycurved blades -projecting from said curved surface and each extendingfrom a point substantially adjacent the axis of the pump to theperiphery thereof, the front edges of said blades being disposed to liein a plane normal to the axis of said pump substantiallythroughout theirlengths, said curved front surface of said impeller being disposed tointersect said normal plane adjacent the axis of said pump and at theinner ends of said blades and to form a substantially conical pointprojecting through said normal plane of said blade edges.

3. A casing assembly for a centrifugal pump having an impeller and anaxial driving shaft, said assembly comprising a substantiallycylindrical supporting section having means adjacent one end forattachment to a stand and having a radial outwardly extending flange atthe other end, a bearing section having an elongated bearing sleeve forsaid driving shaft and extending into the cylindrical portion of thesupporting section in spaced relationthereto, and an outwardly extendingflange secured to the radial ange on the supporting section andconstituting a backing 146 radial outwardly extending ange at the other150 end, a bearing section having an elongated bearing sleeve for saiddriving shaft and extending into the cylindrical portion of thesupporting section in spaced relation thereto and an outwardly extendingange secured in face to face relation to the radial ange on thesupporting section and constituting a backing member for the impellerand dening one Wall of an impeller chamber, said flange on said bearingsection having a diameter substantially equal to the diameter of saidimpeller, and a volute section secured to the rstmentioned ange inconcentric relation to the bearing section ange and dening another wallof said impeller chamber. 1

5. A three part casing assembly for a centrifugal pump having animpeller and an axial driving shaft, the three parts of saidassembly'serving to dene an impeller chamber and a discharge chamber andcomprising a substantially cylindrical supporting section having aradial outwardly extending ange at one end, a bearing section for saidshaft having an elongated bearing sleeve extending into the cylindricalsupporting section in spaced relation thereto and having an outwardlyextending radial iiange of gradually increasing cross-sectionalthickness toward its periphery secured in face to face relation to theradial flange on the supporting section, said bearing section flangeconstituting a backing member for the impeller and having a surfaceconstituting a truste-conical wall for said impeller chamber behind theimpeller, and a volute flange in concentric relation to the bearingsection flange and having surfaces dening another wall of said impellerchamber and the walls of said discharge chamber. y

HAROLD E. BROUGHTON. WILLIAM F. LAMOREAUX.

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